Docker Basic commands

Checking Docker Version

docker version

Checking detailed information

docker info

Note

Docker images can be downloaded from Docker hub using docker commands.

Lets pull an image from docker hub using pull command.

Download a image from docker hub

docker pull <<image name>> 
e.g. docker pull nginx

Verify the downloaded docker images:

docker images ↵

View all the commands that were run with an image via a container.

docker history <<Image Name>>  ↵
e.g. docker history nginx

Remove Docker Images

docker rmi <<Image Name>>  ↵
e.g. docker rmi nginx

Download and run an image in docker container using run command

docker run <<Image Name>>  ↵
e.g. docker run --name nginxservice -d nginx

--name --> to specify a name for the running service. In this example, it is nginxservice

-d --> to run the service in the background

Docker Search

We can also search for the images in the Docker Hub registry by using docker search subcommand. Let us search for ubuntu images in the Docker Hub, and limit the search result only to 20 because we have more than 2000 images on Ubuntu:

docker search ubuntu | head -20

Docker Commands - Container

Now lets run list of commands on the service/ container

List running containers

docker ps

Know the IP address of the running container:

docker inspect <container name> ↵
eg: docker inspect nginxservice

Print the stats for a running Container

docker stats running <<container name>> ↵
e.g. docker stats nginxservice

Pause the processes in a running container

docker pause <<container name>> ↵
e.g. docker pause nginxservice

Unpause the processes in a running container

docker unpause <<container name>> ↵
e.g. docker unpause nginxservice

Kill the processes in a running container

docker kill <<container name>> ↵
e.g. docker kill nginxservices

Start the same container:

docker start <<Container Name>> ↵
e.g. docker start nginxservice

Stop the running container

docker stop <<Container Name >> ↵
e.g. docker stop nginxservice

List all containers (This includes containers in a all states):

We will be able to see the container we just stopped listed here.

docker ps -a

Delete a container:

docker rm <<Container Name >> ↵
e.g. docker rm nginxservice

To remove all stopped containers:

docker container prune

Note:

Instead of using the Container Name, all the above commands can be executed with the container id as well.

Export a container

docker export <<Container Name>> <<file_Name>>.tar ↵
e.g. 
- Lets run a service using docker run command.
docker run --name newnginxservice -d nginx
docker export newnginxservice > test.tar

Import a container

docker import <<Remote URL/Image Name.tar>>  ↵
e.g. docker import test.tar

Stop Docker daemon process

service docker stop

Start Docker daemon process

service docker start Note:

You may not be able to try these 2 commands since you would not have access to root on Katacoda playground.

Diagnose Run Issues

In case you are having a problem with downloading the images and running them, please follow these steps to check whether the docker service is running on your system or not:

Check the running status of docker: service docker stats
Restart Docker service in your system: service docker restart

Yaseen549/docker-basic-commands